AMES, Iowa (AP) — For want of one defensive stop, Iowa State is still winless in the Big 12.

Iowa State led by four points late in the game, but couldn’t hold off Texas Tech one last time and lost 34-31 on Saturday.

Freshman Patrick Mahomes took the Red Raiders on a 75-yard drive that he finished with a 44-yard touchdown pass to Williams with 4:07 left.

“We had a lot of opportunities to finish the game,” ISU cornerback Nigel Tribune said. “That’s one thing we’ve kind of struggled with this year. We haven’t finished games.”

With the loss the Cyclones (2-8, 0-7 Big 12) face the prospect of a winless conference season. They play host to potent West Virginia next Saturday and finish the season at No. 5 TCU on Dec. 6.

It was the third narrow loss this season for Iowa State, which lost those three games by a total of 10 points. This latest was no more difficult to swallow than the others, Tribune said.

“All of them are tough,” he said. “Losses within four points, yeah, it’s pretty tough.”

Mahomes finished with 328 passing yards and four touchdowns in all, including an 82-yarder to Devin Lauderdale that put Tech up 27-24 late in the third quarter. It was the longest play of the season for the Red Raiders (4-7, 2-6 Big 12).

Iowa State regained the lead at 31-27 on Aaron Wimberly’s 3-yard touchdown run early the fourth quarter, but missed a chance to extend the margin when Cole Netten’s 42-yard field goal attempt hooked left.

Tech then marched 75 yards in seven plays for the game-winner, which came when Mahomes found Williams all alone in the right flat and the 228-pounder rambled untouched to the end zone.

The Red Raiders also burned the Cyclones with DeAndre Washington’s 72-yard touchdown run and Williams’ 44-yard run on a fake punt.

“Way too many big plays given up in this football game for us to have a chance to win,” Iowa State coach Paul Rhoads said.

Iowa State drove into Tech territory after Williams’ touchdown but gave up the ball on downs when quarterback Sam Richardson was stopped just short of converting at the Red Raiders’ 31.

“We had a chance to close it out and couldn’t get it done,” Rhoads said. “That’s offense and defense. One more drive, one more stop — we couldn’t get it.”

It was a back-and-forth game and that came as no surprise, given that the league’s two worst defenses were on the field.

Washington rushed for a career-high 181 yards in 18 carries and got the Red Raiders on the scoreboard first when he turned a screen pass from Mahomes into a 26-yard touchdown that included a slew of missed tackles.

Mahomes, who started for the third straight game in place of the injured Davis Webb (ankle), completed 23 of 35 passes with one interception. His other TD pass was a 13-yarder to Lauderdale after the Red Raiders fooled the Cyclones with their fake punt.

On fourth-and-4 from Tech’s 42, the snap went to Williams and he bolted straight up the middle for 44 yards through the surprised defense. Mahomes rolled right on the next play and found Lauderdale in the back of the end zone for a touchdown and the Red Raiders had the momentum after that.

“We were actually in a call to defend a fake they had shown earlier this year to the edge and they went up the middle instead,” Rhoads said. “They executed very well, obviously.”

Richardson went 24 of 38 for 304 yards and two TDs, while Wimberly rushed for 102 yards and scored twice. But the defense couldn’t hold up and Tech finished with 600 total yards.

It also didn’t help that the usually reliable Netten missed two of three field goal attempts. He kicked a 22-yarder to give ISU at 17-14 halftime lead, its first lead at the break since the second game of the year, but was wide right on an earlier 41-yard attempt.

The first he simply miss-hit. The second?

“It was really a solid hit,” he said. “So I was kind of surprised when it went over to the left.”